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Background: Pancreatic cystic lesions (PCLs) are frequent on MRI and are thought to be associated with pancreatic adenocarcinoma (PDAC) necessitating long‐term surveillance based on older studies suffering from selection bias. Purpose: To establish the percentage of patients with PCLs on MRI with a present or future PDAC. Study Type: Systematic review, meta‐analysis. Population: Adults with PCLs on MRI and a present or future diagnosis of PDAC were eligible. MEDLINE, EMBASE, Cochrane Central Register of Controlled Trials, and Scopus were searched to April 2022 (PROSPERO:CRD42022320502). Studies limited to PCLs not requiring surveillance, <100 patients, or those with a history/genetic risk of PDAC were excluded. Field Strength/Sequence: ≥1.5 T with ≥1 T2‐weighted sequence. Assessment: Two investigators extracted data, with discrepancies resolved by a third. QUADAS‐2 assessed bias. PDAC was diagnosed using a composite reference standard. Statistical Tests: A meta‐analysis of proportions was performed at the patient‐level with 95% confidence intervals (95% CI). Results: Eight studies with 1289 patients contributed to the percentage of patients with a present diagnosis of PDAC, and 10 studies with 3422 patients to the percentage with a future diagnosis. Of patients with PCLs on MRI, 14.8% (95% CI 2.4–34.9) had a PDAC at initial MRI, which decreased to 6.0% (2.2–11.3) for studies at low risk of bias. For patients without PDAC on initial MRI, 2.0% (1.1–3.2) developed PDAC during surveillance, similar for low risk of bias studies at 1.9% (0.7–3.6), with no clear trend of increased PDAC for longer surveillance durations. For patients without worrisome features or high‐risk stigmata, 0.9% (0.1–2.2) developed PDAC during surveillance. Of 10, eight studies had a median surveillance ≥3 years (range 3–157 months). Sources of bias included retrospectively limiting PCLs to those with histopathology and inconsistent surveillance protocols. Data Conclusion: A low percentage of patients with PCLs on MRI develop PDAC while on surveillance. The first MRI revealing a PCL should be scrutinized for PDAC. Level of Evidence: 3 Technical Efficacy: Stage 2 [ABSTRACT FROM AUTHOR]

Fibrosis is the aberrant process of connective tissue deposition from abnormal tissue repair in response to sustained tissue injury caused by hypoxia, infection, or physical damage. It can affect almost all organs in the body causing dysfunction and ultimate organ failure. Tissue fibrosis also plays a vital role in carcinogenesis and cancer progression. The early and accurate diagnosis of organ fibrosis along with adequate surveillance are helpful to implement early disease-modifying interventions, important to reduce mortality and improve quality of life. While extensive research has already been carried out on the topic, a thorough understanding of how this relationship reveals itself using modern imaging techniques has yet to be established. This work outlines the ways in which fibrosis shows up in abdominal organs and has listed the most relevant imaging technologies employed for its detection. New imaging technologies and developments are discussed along with their promising applications in the early detection of organ fibrosis. [ABSTRACT FROM AUTHOR]

Fibrosis is a pathological process involving the abnormal deposition of connective tissue, resulting from improper tissue repair in response to sustained injury caused by hypoxia, infection, or physical damage. It can impact any organ, leading to their dysfunction and eventual failure. Additionally, tissue fibrosis plays an important role in carcinogenesis and the progression of cancer. Early and accurate diagnosis of organ fibrosis, coupled with regular surveillance, is essential for timely disease-modifying interventions, ultimately reducing mortality and enhancing quality of life. While extensive research has already been carried out on the topics of aberrant wound healing and fibrogenesis, we lack a thorough understanding of how their relationship reveals itself through modern imaging techniques. This paper focuses on fibrosis of the genito-urinary system, detailing relevant imaging technologies used for its detection and exploring future directions. [ABSTRACT FROM AUTHOR]

Sustained injury from factors such as hypoxia, infection, or physical damage may provoke improper tissue repair and the anomalous deposition of connective tissue that causes fibrosis. This phenomenon may take place in any organ, ultimately leading to their dysfunction and eventual failure. Tissue fibrosis has also been found to be central in both the process of carcinogenesis and cancer progression. Thus, its prompt diagnosis and regular monitoring is necessary for implementing effective disease-modifying interventions aiming to reduce mortality and improve overall quality of life. While significant research has been conducted on these subjects, a comprehensive understanding of how their relationship manifests through modern imaging techniques remains to be established. This work intends to provide a comprehensive overview of imaging technologies relevant to the detection of fibrosis affecting thoracic organs as well as to explore potential future advancements in this field. [ABSTRACT FROM AUTHOR]

The primary purpose of this study was to assess the interreader reliability of a grading system for UIP based on the quantification of normal lung. This grading system considers each of the following lung regions: right upper and middle lobes, right lower lobe, left upper lobe, and left lower lobe. Each is assigned a grade based on the following: 0: 0% normal lung; 1: 1–49% normal lung; 2: 50–74% normal lung; 3: 75–89% normal lung; 4: 90–99% normal lung; 5: 100% normal lung. The secondary purpose was to compare the grades rendered by non-cardiothoracic subspecialty trained radiologists to grades established by cardiothoracic radiologists, which were considered the gold standard. Chest CT images of patients were obtained by searching the radiology record system for the terms "usual interstitial pneumonia" and "UIP". Each case was confirmed by radiologist review; pathology was not assessed given the small fraction of cases that underwent biopsy due to the high risk of complications in patients with fibrotic lung disease. Two cardiothoracic radiologists evaluated each CT and reached a consensus grade. Two different radiologists who were not subspecialty trained in cardiothoracic radiology independently graded each case. Spearman correlation analysis was performed to compare the two reader's grades as well as each reader's grade independently to the gold standard score. Our analysis demonstrated a strongly positive statistically significant interreader correlation coefficient (RS) = 0.7062, P < 0.001. Our analysis of each reader compared to the gold standard demonstrated an Rs = 0.77559, P < 0.001 and an RS = 0.69958, P < 0.001 for readers 1 and 2, respectively, both representing statistically significant strongly positive correlations. These results demonstrate strong interreader reproducibility and show that radiologists without subspecialty training in cardiothoracic radiology render grades that correlate strongly with those given by cardiothoracic radiologists. These findings support the use of this grading system for UIP both to monitor clinical progression and as a surrogate endpoint for antifibrotic drug trials. [ABSTRACT FROM AUTHOR]

Homologous recombination repair (HRR) pathway deficiency opens multiple therapeutic avenues within pancreatic cancer. Patients with HRR deficiency–associated gene mutations such as BRCA1 , BRCA2 , and PALB2 are more susceptible to platinum-based chemotherapies and in those with somatic BRCA mutations, PARP inhibitor therapy prolongs progression-free survival. The case discussed herein illustrates the therapeutic opportunities offered through the identification of HRR deficiency in pancreatic cancer, as well as the challenges associated with treatment and prevention of central nervous system metastases in long-term survivors of pancreatic cancer. [ABSTRACT FROM AUTHOR]

This manuscript is part of the ileal pouch symposium and will describe the water-soluble contrast enema, CT, and small bowel series. MRI and other imaging modalities are discussed elsewhere in the symposium. Water-soluble contrast enema and CT are excellent for the evaluation of the ileal pouch. Contrast enema and CT with anal contrast administration can allow for anastomotic integrity and pouch assessment. Pre-pouch ileum, extra-intestinal manifestations, and acute symptomatology are best assessed with CT. The contrast small bowel examination is of limited utility in pouch patients and should not be performed. Indications, imaging technique, and anatomic pouch assessment with water-soluble contrast enema, CT, and contrast small bowel examination will be reviewed here. [ABSTRACT FROM AUTHOR]

Although much radiologic literature has focused on the short-term post-operative complications associated with ileal pouches, as the number of patients with long-term pouches has grown, there is increasing realization of the functional deficits that may occur long after pouch creation. Dynamic pouch imaging using fluoroscopy and MRI can provide assessment of the underlying causes of symptomatic pouch dysfunction and can provide critical insight to the management of this complex patient population. In this paper, we provide an overview of the unique problems encountered in patients with long-term ileal pouches, and provide an overview of the techniques, interpretation, and reporting for fluoroscopic and MR pouch defecography. [ABSTRACT FROM AUTHOR]

Purpose: Surgical resection is the only potential curative treatment for patients with pancreatic ductal adenocarcinoma (PDAC), but unfortunately most patients recur within 5 years of surgery. This article aims to assess the practice patterns across major academic institutions and develop consensus recommendations for postoperative imaging and interpretation in patients with PDAC. Methods: The consensus recommendations for postoperative imaging surveillance following PDAC resection were developed using the Delphi method. Members of the Society of Abdominal Radiology (SAR) PDAC Disease Focused Panel (DFP) underwent three rounds of surveys followed by live webinar group discussions to develop consensus recommendations. Results: Significant variations currently exist in the postoperative surveillance of PDAC, even among academic institutions. Differentiating common postoperative inflammatory and fibrotic changes from tumor recurrence remains a diagnostic challenge, and there is no reliable size threshold or growth rate of imaging findings that can provide differentiation. A new liver lesion or peritoneal nodule should be considered suspicious for tumor recurrence, and the imaging features should be interpreted in the appropriate clinical context (e.g., CA 19–9, clinical presentation, pathologic staging). Conclusion: Postoperative imaging following PDAC resection is challenging to interpret due to the presence of confounding postoperative inflammatory changes. A standardized reporting template for locoregional findings and report impression may improve communication of relaying risk of recurrence with referring providers, which merits validation in future studies. [ABSTRACT FROM AUTHOR]

Background: Patients with SARS-CoV-2 who present with gastrointestinal symptoms have a milder clinical course than those who do not. Risk factors for severe COVID-19 disease include increased adiposity and sarcopenia. Aims: To determine whether body composition risk factors are associated with worse outcomes among patients with gastrointestinal symptoms. Methods: This was a retrospective study of hospitalized patients with COVID-19 who underwent abdominal CT scan for clinical indications. Abdominal body composition measures including skeletal muscle index (SMI), intramuscular adipose tissue index (IMATI), visceral adipose tissue index (VATI), subcutaneous adipose tissue index (SATI), visceral-to-subcutaneous adipose tissue ratio (VAT/SAT ratio), and liver and spleen attenuation were collected. The association between body composition measurements and 30-day mortality was evaluated in patients with and without gastrointestinal symptoms at the time of positive SARS-CoV-2 test. Results: Abdominal CT scans of 190 patients with COVID-19 were evaluated. Gastrointestinal symptoms including nausea, vomiting, diarrhea, or abdominal pain were present in 117 (62%). Among patients without gastrointestinal symptoms, those who died had greater IMATI (p = 0.049), less SMI (p = 0.010), and a trend toward a greater VAT/SAT ratio. Among patients with gastrointestinal symptoms, those who died had significantly greater IMATI (p = 0.025) but no differences in other measures. Conclusions: Among patients with COVID-19, those without gastrointestinal symptoms showed the expected associations between mortality and low SMI, high IMATI, and trend toward higher VAT/SAT ratio, but those with gastrointestinal symptoms did not. Future studies should explore the mechanisms for the altered disease course in patients with COVID-19 who present with gastrointestinal symptoms. [ABSTRACT FROM AUTHOR]

Background Gastroenteropancreatic neuroendocrine tumors (GEP-NETs) are rare neoplasms with an increasing annual incidence and prevalence. Many are metastatic at presentation or recur following surgical resection and require systemic therapy, for which somatostatin analogs such as octreotide or lanreotide comprise typical first-line therapies. Nonetheless, treatment options remain limited. Epigenetic processes such as histone modifications have been implicated in malignant transformation and progression. In this study, we evaluated the anti-proliferative effects of a histone deacetylase (HDAC) inhibitor, entinostat, which was computationally predicted to show anti-cancer activity, as confirmed in in vitro and in vivo models of GEP-NETs. Methods This was a phase II study to evaluate the efficacy and safety of entinostat in patients with relapsed or refractory abdominal NETs. The primary objective was to estimate the objective response rate to entinostat. Additionally, with each patient as his/her own control we estimated the rates of tumor growth prior to enrollment on study and while receiving entinostat. Patients received 5 mg entinostat weekly until disease progression or intolerable toxicity. The dose could be changed to 10 mg biweekly for patients who did not experience grade ≥ 2 treatment-related adverse events (AEs) in cycle 1, but was primarily administered at the starting 5 mg weekly dose. Results The study enrolled only 5 patients due to early termination by the drug sponsor. The first patient that enrolled had advanced disease and died within days of enrollment before follow-up imaging due to a grade 5 AE unrelated to study treatment and was considered non-evaluable. Best RECIST response for the remaining 4 patients was stable disease (SD) with time on study of 154+, 243, 574, and 741 days. With each patient as his/her own control, rates of tumor growth on entinostat were markedly reduced with rates 17%, 20%, 33%, and 68% of the rates prior to enrollment on study. Toxicities possibly or definitely related to entinostat included grade 2/3 neutrophil count decrease [2/4 (50%)/ 2/4 (50%)], grade 3 hypophosphatemia [1/4, (25%)], grade 1/2 fatigue [1/4 (25%)/ 2/4 (50%)], and other self-limiting grade 1/2 AEs. Conclusion In the treatment of relapsed or refractory abdominal NETs, entinostat 5 mg weekly led to prolonged SD and reduced the rate of tumor growth by 32% to 83% with an acceptable safety profile (ClinicalTrials.gov Identifier: NCT03211988). [ABSTRACT FROM AUTHOR]

Purpose: We aimed to explore potential confounders of prognostic radiomics signature predicting survival outcomes in clear cell renal cell carcinoma (ccRCC) patients and demonstrate how to control for them. Materials and Methods: Preoperative contrast enhanced abdominal CT scan of ccRCC patients along with pathological grade/stage, gene mutation status, and survival outcomes were retrieved from The Cancer Imaging Archive (TCIA)/The Cancer Genome Atlas—Kidney Renal Clear Cell Carcinoma (TCGA-KIRC) database, a publicly available dataset. A semi-automatic segmentation method was applied to segment ccRCC tumors, and 1,160 radiomics features were extracted from each segmented tumor on the CT images. Non-parametric principal component decomposition (PCD) and unsupervised hierarchical clustering were applied to build the radiomics signature models. The factors confounding the radiomics signature were investigated and controlled sequentially. Kaplan–Meier curves and Cox regression analyses were performed to test the association between radiomics signatures and survival outcomes. Results: 183 patients of TCGA-KIRC cohort with available imaging, pathological, and clinical outcomes were included in this study. All 1,160 radiomics features were included in the first radiomics signature. Three additional radiomics signatures were then modelled in successive steps removing redundant radiomics features first, removing radiomics features biased by CT slice thickness second, and removing radiomics features dependent on tumor size third. The final radiomics signature model was the most parsimonious, unbiased by CT slice thickness, and independent of tumor size. This final radiomics signature stratified the cohort into radiomics phenotypes that are different by cancer-specific and recurrence-free survival; HR (95% CI) = 3.0 (1.5–5.7), p <0.05 and HR (95% CI) = 6.6 (3.1–14.1), p <0.05, respectively. Conclusion: Radiomics signature can be confounded by multiple factors, including feature redundancy, image acquisition parameters like slice thickness, and tumor size. Attention to and proper control for these potential confounders are necessary for a reliable and clinically valuable radiomics signature. [ABSTRACT FROM AUTHOR]

There have been many publications detailing imaging features of malignant transformation of intraductal papillary mucinous neoplasms (IPMN), management and recommendations for imaging follow-up of diagnosed or presumed IPMN. However, there is no consensus on several practical aspects of imaging IPMN that could serve as a clinical guide for radiologists and enable future data mining for research. These aspects include how to measure IPMN, define reporting terminology, standardize reporting and unify guidelines for surveillance. The Society of Abdominal Radiology (SAR) created multiple Disease-Focused Panels (DFP) comprised multidisciplinary panel members who focus on a particular disease, with the goal to develop ways for radiologists to improve patient care, education, and research. DFP members met to identify the current controversies and limitations of imaging pancreatic IPMN. This paper aims to provide a practical review of the key imaging characteristics of IPMN for trainees and practicing radiologists, to guide uniformity of performance and interpretation of surveillance imaging studies, and to improve communication with clinicians by providing a lexicon and reporting template based on the experience of the SAR-DFP panel members. [ABSTRACT FROM AUTHOR]

Purpose: The purpose of our research is to evaluate the usefulness of chest X-ray for triaging patients with suspected COVID-19 infection. Methods: IRB approval was obtained to allow a retrospective review of adult patients who presented to the Emergency Department with a complaint of fever, cough, dyspnea or hypoxia and had a chest X-ray between 12 March 2020 and 26 March 2020. The initial chest X-ray was graded on a scale of 0–3 with grade 0 representing no alveolar opacities, grade 1: < 1/3 alveolar opacities of the lung, Grade 2: 1/3 to 2/3 lung with alveolar opacities and grade 3: > 2/3 alveolar opacities of the lung. Past medical history of diabetes and hypertension, initial oxygen saturation, COVID-19 testing results, intubation, and outcome were also collected. Results: Four hundred ten patient chest X-rays were reviewed. Oxygen saturation and X-ray grade were both significantly associated with the length of stay in hospital, the hazard ratio (HR) of discharge was 1.05 (95% CI [1.01, 1.09], p = 0.017) and 0.61 (95% CI [0.51, 0.73], p < 0.001), respectively. In addition, oxygen saturation and X-ray grade were significant predictors of intubation (odds ratio (OR) of intubation is 0.88 (95% CI [0.81, 0.96], p = 0.004) and 3.69 (95% CI [2.25, 6.07], p < 0.001). Conclusions: Initial chest X-ray is a useful tool for triaging those subjects who might have poor outcomes with suspected COVID-19 infection and benefit most from hospitalization. [ABSTRACT FROM AUTHOR]

The visceral organs of the male pelvis have complex anatomic relationships with the surrounding extraperitoneal spaces, supplying arteries and adjacent pelvic musculature. Since various neoplastic, vascular, and traumatic pathologies can often involve multiple organs and spread into adjacent pelvic spaces, a keen understanding of this intricate anatomy can help radiologists to accurately characterize findings and improve recognition of the routes in which these conditions can spread. The purpose of this review is to examine the relationships between the anatomic compartments of the pelvic extraperitoneal space, summarize the pelvic arterial anatomy, and identify the pelvic muscles that support normal genitourinary function. [ABSTRACT FROM AUTHOR]

Purpose: To enhance clinician's decision-making by diagnosing hepatocellular carcinoma (HCC) in cirrhotic patients with indeterminate liver nodules using quantitative imaging features extracted from triphasic CT scans.Material and Methods: We retrospectively analyzed 178 cirrhotic patients from 27 institutions, with biopsy-proven liver nodules classified as indeterminate using the European Association for the Study of the Liver (EASL) guidelines. Patients were randomly assigned to a discovery cohort (142 patients (pts.)) and a validation cohort (36 pts.). Each liver nodule was segmented on each phase of triphasic CT scans, and 13,920 quantitative imaging features (12 sets of 1160 features each reflecting the phenotype at one single phase or its change between two phases) were extracted. Using machine-learning techniques, the signature was trained and calibrated (discovery cohort), and validated (validation cohort) to classify liver nodules as HCC vs. non-HCC. Effects of segmentation and contrast enhancement quality were also evaluated.Results: Patients were predominantly male (88%) and CHILD A (65%). Biopsy was positive for HCC in 77% of patients. LI-RADS scores were not different between HCC and non-HCC patients. The signature included a single radiomics feature quantifying changes between arterial and portal venous phases: DeltaV-A_DWT1_LL_Variance-2D and reached area under the receiver operating characteristic curve (AUC) of 0.70 (95%CI 0.61-0.80) and 0.66 (95%CI 0.64-0.84) in discovery and validation cohorts, respectively. The signature was influenced neither by segmentation nor by contrast enhancement.Conclusion: A signature using a single feature was validated in a multicenter retrospective cohort to diagnose HCC in cirrhotic patients with indeterminate liver nodules. Artificial intelligence could enhance clinicians' decision by identifying a subgroup of patients with high HCC risk.Key Points: • In cirrhotic patients with visually indeterminate liver nodules, expert visual assessment using current guidelines cannot accurately differentiate HCC from differential diagnoses. Current clinical protocols do not entail biopsy due to procedural risks. Radiomics can be used to non-invasively diagnose HCC in cirrhotic patients with indeterminate liver nodules, which could be leveraged to optimize patient management. • Radiomics features contributing the most to a better characterization of visually indeterminate liver nodules include changes in nodule phenotype between arterial and portal venous phases: the "washout" pattern appraised visually using EASL and EASL guidelines. • A clinical decision algorithm using radiomics could be applied to reduce the rate of cirrhotic patients requiring liver biopsy (EASL guidelines) or wait-and-see strategy (AASLD guidelines) and therefore improve their management and outcome. [ABSTRACT FROM AUTHOR]

Abdominal CT is often the first imaging modality used to characterize the primary tumor (including invasion of vasculature) and identify metastatic lesions. Finally, functional imaging with somatostatin receptor scintigraphy or SP 68 sp Ga-DOTATATE PET/CT can identify lesions not seen on either CT or MRI and help differentiate pNET from neuroendocrine carcinoma. In this case, SP 68 sp Ga-DOTATATE PET/CT was not necessary since the tumor was localized by CT and confirmed by endoscopic ultrasound without findings suggestive of occult metastatic disease. [Extracted from the article]

Radiographic series of the foot are often obtained in conjunction with ankle X-rays when the clinical presentation is limited to trauma to the ankle. The Ottawa Ankle and Foot Rules were established in 1992 and serve as reliable guidelines to determine when an ankle or foot series is warranted in patients who have sustained minor ankle and/or foot injury. We retrospectively reviewed radiographic studies of all patients over a period of 18 months who simultaneously had ankle and foot plain radiographs performed for acute complaints limited to the ankle alone. Of the 243 patients who met our inclusion criteria, 55 patients had fractures, 46 in or near the ankle joint, and nine which were located at the base of the fifth metatarsal bone. No fractures or dislocations were noted elsewhere in the foot. All of the fifth metatarsal fractures were evident on adequately performed ankle series. Our findings suggest that films of the foot are not necessary when trauma is limited to the ankle and when an appropriately performed ankle series has been completed. [ABSTRACT FROM AUTHOR]